Should I use HEET or ISO-HEET?
For Diesel engines, use ISO-HEET® (red bottle), or HEET® Diesel. ISO-HEET® is formulated for all engine and fuel types, with the additional benefit of an injector cleaner for year-round protection. Using HEET® is quite simple – open the bottle, pour it into your full fuel tank. What is the difference between ISO-HEET and HEET? YELLOW - WHAT IS THE DIFFERENCE? ISO-HEET® Brand (red) is a premium water remover and injector cleaner that can be used all year-round and can be used in all types of gasoline, 2-cycle mix and DIESEL.